Limit language options to English and Vietnamese

The language switcher now only offers 'en' and 'vi' as selectable languages, reducing the list from nine to two. This may be for a more focused user experience or to match current localization support.

Author: DongDuong2001

components/language-switcher.tsx

@@ -12,7 +12,7 @@ export function LanguageSwitcher() {
     setCurrentLang(getUserLanguage())
   }, [])
 
-  const languages: Language[] = ["en", "es", "fr", "de", "zh", "ja", "pt", "ru", "vi"]
+  const languages: Language[] = ["en", "vi"]
 
   const handleLanguageChange = (lang: Language) => {
     setUserLanguage(lang)